The Rolling-wave Planning

Abstract

It is not often possible to foresee the future activities in a project with consistent detail over the entire period of the project. Therefore, project managers faced with unexpected events employ a “rolling wave” approach to planning. The rolling-wave Planning is a project management technique that requires iterative planning to “roll out” detailed plans for the near term and reevaluate the plan regularly as the project proceeds.The Rolling Wave Planning technique uses progressive elaboration, which is the act of elaborating the work packages in greater detail as the project unfolds.
It is necessary to provide key milestones and assumptions as they will help stakeholders see the reason for using Rolling Wave Planning and what to expect as the project progresses. As the project progresses, the risks, assumptions, and milestones originally identified become more defined and reliable. Rolling Wave Planning focuses the team on the short-term goals, course correcting as needed. The rolling-wave planning is particularly useful in projects with high uncertainty.It is a good idea to have an understanding of the “big blocks” without detailing exactly the scope of the project. The article will introduce the definition of the Rolling Wave Planning and provide the guidelines to develop it. The article will also provide a brief overview of the literature and area where the Rolling Wave can be applied, along with its limitations and benefits.

Introduction

Mountain Climber Analogy

How often have you been asked for estimates of the duration and the cost of a project and have given answers before you really fully understood the scope of the effort? It's related to the discussion of how this scenario develops, why this approach seldom works, and what can be done to structure a more realistic alternative. To address this issue, consider an analogy: Imagine that you are an expert mountain climber, standing at the bottom of an imposing mountain you've never seen before. It's your job to climb over this mountain and reach the bottom on the other side. The person who is funding your expedition asks you “How long will it take you to climb over and get to the bottom on the other side of the mountain, and what resources will you need?” “I don’t know” wouldn’t be a satisfactory answer to your sponsors because they hired you for your expertise in mountain climbing and expects you to come forth with some reasonable answers. On the other hand, if you shoot from the hip, you know the accuracy of your guess will be weak at best, and sooner or later you will have to confront your error. In this case, the rolling wave is an alternative way. This method can both satisfy your sponsor and add a sense of integrity and credibility to your commitments. At the beginning of the climb, you stand at the bottom of the mountain, with minimal knowledge of what confronts you. But your mountain climbing background and experience, combined with historic data gathered from other people who have tried to climb this mountain, allows you to approximate the time and resources required. Note the term is approximate, not estimate. When approximating, afford all the flexibility possible.

Rolling Wave Characteristics

• Progressive elaboration: a project management technique that involves progressive elaboration to add detail to the Work Breakdown Structure (WBS) on an ongoing basis. For example, Phases 1-2 might be broken down fully in the WBS. Phases 3-6 might be outlined only to the level of subprojects. Then, while schedule activities for phase 1 are underway, the detailed planning for phase 3 would commence. As phase 2 is put in motion, planning for phase 4 would start and so forth. These concepts address the idea that planning near term work in detail and later work in less detail. Then as new details emerge, going back to the plans and updating them with the new data.
• Shorten time: Rolling wave or adaptive planning is a key idea in agile methods.[3] This technique may also help shorten time to completion in 2 ways: 1) By making it possible for productive activities to begin without waiting for every detail of the project work to be determined in advance. 2) By eliminating downtime for additional planning in the middle of a project since planning is done continuously.

Rolling Wave Planning vs. Predictive Planning

One of the big ideas of agile and iterative development is to adapt based on feedback, and this is not only with respect to requirements and design, but also the plan or schedule. Adaptive planning in IID methods is a refinement of the well-known rolling wave planning concept—more on this later.
In contrast, predictive planning implies there would be such an iteration-by-iteration plan to the project end. In adaptive planning, there are milestones with dates, (or at least, there can be) but the path of iterations to those milestones is left flexible or adaptive. And, the milestones themselves may change if in the best interest of the project. Predictive planning would go further than this, it would speculate a week-by-week or iteration-by-iteration schedule of the path to these milestones.